I have a question. How big do you think the population of patients is that is a good candidate for a Harmony but not a good candidate for Altera and vice versa? And do you think people who are implanting should get experience with one device or try to use both devices, and how would you pick cases for one or the other in that sense? I don't have an answer to that question, and I think John touched on it earlier. What you're really asking is, do we need multiple technologies to address the issue of pulmonary regurgitation in our population? The answer to that is yes. I think there's enough variability that we're probably going to need more than one, certainly. Do we need three or four? I think that's probably too much. If you take Harmony compared to Altera, are there advantages and disadvantages to each relative to one another? The answer is yes. But I don't think I know enough now, or maybe others do, which patients are going to be better served. And the answer really is not going to be known until we get this prolonged 10-year follow-up data where we really see the difference in outcomes. If there is a difference in outcomes, how much infection do we see? How much arrhythmia is there? How much device-related trauma is there? So we're in a really fun time because there's going to be a lot of opinions. I know John has opinions, and Shabana has opinions, and Amy's going to have opinions, but none of us know yet. So it's not going to stop us from sharing our opinions. But we really won't know, honestly, for a while. I think we definitely need two families of technologies at a minimum. Maybe there's room for a third. John, what do you think? I agree, Matt. I think, like I said, I think that we're beyond proof-of-concept phase, and in some ways what's been really interesting is how incredibly well these valves have performed when we'll – well, I say we all, but the older ones of us, and I'll include you in that, Matt. We remember Melody and all the talk about moving over into native outflow tracts and how much concern and hand-wringing there was. As I say, I think it's incredible how these technologies have performed, and now we're beyond that. We've got to start mining the granularity, and I think it's going to take time. If anything worries me, it's the fact that all of these technologies look very similar. They're all based on this cotton reel-type technology, and I think that what I hope is that we see maybe some different types of valve technology coming into the market, which will help us then tackle the pyramidal outflow tract and the smallish PAs and all these sorts of things. But it's an exciting time to be in this field because this is going to be the story of our lives as interventionalists, I think, for the next generation, and it's a really exciting time. I agree. My prediction is that unless we end up being tripped up by endocarditis and the things that got Melody, I think that this will replace surgical valve replacement in our time, for sure. You're not going to get an argument on this panel about that. I think to add is a question about how many technologies does someone need to learn. Now, I would say it depends on what your volume is. If you're going to do only one case a year, and if that case ends up being a good fit for either, you might not have the benefit of learning all of them. But I think the nice thing about this community and what the industry has done is they support you really well with clinical specialists and have proctors involved. You can call up Matt or John or Amy. Don't call me, but for advice on putting these devices in or which one's a great anatomy. So I think you have the opportunity of being supported for any device you want to learn, but it depends on your volume and what exposure you get. Can I ask you a follow-up question about your detox? A lot of the data you showed is sort of from the pre-self-expanding valve era. How do you approach borderline sort of a similar question? How do you approach patients who could be either have a balloon expandable or self-expanding, especially at the lower end? Say somebody's minimal alpha tritameters to 23 or something. Do you balloon size and then decide or do you just decide beforehand? I mean, if it is 23, then for me, it's going to be a balloon expandable. I still believe just having had the exposure and the ability to learn all, I mean, both the self-expanding valves, there is benefit and merit to having lesser metal within the RBOT if possible. That being said, when it comes to 28 by 29, we used to push the envelope with the larger sapien valves with more volumes or larger balloons. That we don't do anymore. We did take a risk with potential embolization. So those are the ones I think I'd still endow. But if you're able to safely put a 29 and not anything smaller, then absolutely. We don't have time to debate this, Shabana, but that's an interesting point. I disagree that balloon expandables are better than self-expanding devices in these patchless dilated outflow tracks for a variety of reasons. I have an opinion about it, but no fact. I think that so maybe, Konstantin, you'd plan another webinar and we can kick that around because I'm sure, you know, anyhow, I'm not going to bore everybody with why I think there's an advantage to sort of putting these larger frames into these outflow tracks and making them more uniform down the line. I just think there's some advantage there that I'm not going to articulate now because it's too late. But maybe down the line, we can talk about that. And then just one last question. Does anybody have an age or weight limit for patients who meet indications for a valve like a 12-year-old or 11-year-old as a big RV? I know they're the minority, but we do see them. So how do you think about that? I'll kick off with that. I think that, again, these are the sorts of debates that we're getting into. I think we've gone through that wildly enthusiastic phase where we prove the concept and we put these valves in everyone. We do have to think about a lifetime strategy for these patients. You know, and a 12-year-old getting an Ultera, Harmony, whatever it is, you are effectively taking out that outflow tracks. And if they then come to surgery, it's a big deal. So I don't know where the line is, Constantine. I don't know at what point we should be saying too young, too small. But I certainly think that it's incumbent on us to start thinking about this very seriously. Otherwise, we may be setting up a whole bunch of kids for real trouble when they get into their 30s, 40s, and 50s. Yeah. In principle, generally speaking, I deal with that. Right now, loosely, if you're after durability with these new devices as you put them in, what's going to fail on them most likely is the leaflets, right? So just leaflet degradation over time. And my read on the surgical retrospective data on tissue valve leaflets in the pulmonary outflow tract is somewhere in your mid-teens, the predictability of valve durability begins to increase and begins to reflect what you see in adult populations. And so I'm comfortable saying to families, I expect these valve leaflets to be, based on the retrospective look at the surgical experience with surgical tissue valves, I think these leaflets should be functional for 8 to 10 years before we need to talk about reintervention. And that transition seems to be somewhere in the mid-teens around age 15, roughly, is how I interpret that. So when I get younger than 15, I start thinking, wow, I don't want to put this in because the leaflets could break down pretty quickly. We've all had that experience where you put a valve in, surgical valve or catheter-based valve, and, you know, six months or a year later, it's already leaking or asthmatic, especially in the sub-10-year-old populations. But in that sort of tweener years, there's a transition happens that I think that's how I do it. So 15 is kind of what I mentally target that I start to get comfortable about the leaflet durability question. But of course, you have to go earlier sometimes because you see young patients with big old boggy RVs because of PR. So you're forced to do it. But that conversation is very different with that family about how long I expect this device to last. All right. Well, thank you, everybody, for participating. I don't see any more questions in the chat. So I appreciate everybody's time and input and great discussions and obviously lots more to learn and debate.

Harmony device

Altera device

patient population

valve technology

surgical valve replacements